The present invention relates to a plain bearing, which comprises a backing alloy made of copper alloy or aluminum alloy and a coat layer of synthetic resin formed on the surface of the backing alloy, and to a process for producing the same.
Generally, plain bearings for use in internal combustion engines, etc. are often exposed to severe use conditions such as high speed revolution, heavy load, etc. So far proposed plain bearings capable of meeting use in such severe conditions include, for example, a plain bearing comprising a backing alloy made of copper alloy, aluminum alloy, or the like and a coat layer formed on the surface of the backing alloy, as disclosed in JP-A-2000-136397. Such a plain bearing has an improved sliding property, because the coat layer is formed from polyimide or polyamideimide as a base resin, which further contains polytetrafluoroethylene and graphite as solid lubricants.
However, requirements for further improvement of the sliding property of plain bearings have been recently imposed to meet higher power output, higher performance, etc. of plain bearings for use in internal combustion engines, etc., but the aforementioned conventional plain bearings have found unsatisfactory for attaining the required performances, particularly reduction in the coefficient of friction, improvement of conformability and anti-seizure characteristics, etc.